I was wrongly ticketed in Celina Texas for a minor ...

I was wrongly ticketed in Celina Texas for a minor child not being in a safty restrint.  Do I have a chance to argue this and get it dropped. I drive a 2006, lifted, Ford F-150, Supercrew truck, my grandson was riding in the front passenger side with the window down. It was 3 PM, on a bright sunny day.  When I drive any where with my kindergarten age grandson I always make an almost assenine seat belt issue.  After leaving his school area and approching a stop sign in a school zone, my grandson who had been eating a mint announced "he dropped it but got it back," I clapped and said "Yea" I observed him fully latched in his seat belt, I looked up, saw an officer standing about 3 feet to the roadside, the officer motioned me to pull over, after approaching my truck he condecendingly asked "You know why I pulled you over right?" I gave a quizzicle "No" which instantly made him frustrated, (which after the fact, I can empathize as I think he thought I was trying to pull a fast one on him) he authoritatively stated, "He saw the seat belt latch in his hand!"  and accused me of calling him a liar when I protested he then quizzed my granson whom told him he dropped the mint, near the latch, unhooked it , got it out and quickly latched it back.  That is how fast my grandson did it, I never saw him do this or heard a click of the belt either time (unlatching or relatching) all I knew was he told me "he dropped it then got it" he was never never out of the restraint device.